Edit: Google Photos Screensaver and Norton Security Scan has been removed from the Google Pack, and the links are no longer valid, but the links have been kept for "historical" reasons.

Note: This post was previously posted under the title: "Installing progams from the Google Pack, without using the Google Updater program".

Most of the programs in the Google Pack could be installed without using the Google Updater program, but there is three one exceptions: Spyware Doctor Starter Edition, Norton Security Scan and Google Photos Screensaver, you can’t install any of these this programs without using the Google Updater program.
The version of Spyware Doctor that you could download from the Spyware Doctor website is limited to only scanning your computer, but not removing spywares.